Download Do biogenic volatile organic compound (bVOC) emissions vary from

Do biogenic volatile organic compound (bVOC) emissions vary from different
tree species in short-rotation forest (SRF) ecosystems?
N.B. This project has CASE funding from Forest Research
Dr Julia Drewer, NERC Centre for Ecology & Hydrology, Bush Estate ([email protected])
Dr Mathew Heal, School of Chemistry, University of Edinburgh ([email protected])
Dr James Morison, Forest Research, Alice Holt Lodge ([email protected])
Project background
The EU has a mandatory target for 20% of all energy to be generated from renewable
sources by 2020. Biomass is seen as a key contributor to meeting this aim, and the planting
of short-rotation forestry (SRF) has the potential to provide some of that biomass
requirement. Many broadleaf species such as alder, ash, birch and poplar, and conifers such
as Scots pine and Sitka spruce, as well as exotic species such as eucalyptus are currently
being grown in SRF trials. It is important that we
understand all aspects of how such plantations may
impact on the environment. One aspect is the emission
from the vegetation and ground litter of reactive biogenic
volatile organic compounds (bVOC), particularly isoprene
and monoterpenes, which contribute to the formation of
ozone and particles in the atmosphere, with implications
for air quality and climate change. Despite considerable
research on isoprene emissions from many ecosystems,
the magnitude and controls of bVOC emissions from
biofuel mono-cultures still need to be investigated.
Eucalyptus and conifers, in particular, are likely to be
strong emitters of bVOCs to the atmosphere. This project
builds upon previous CEH & UoE studies investigating
trace gas emissions from short-rotation coppice willow
and Miscanthus bioenergy crops in the UK (Copeland et
Example of short-rotation biofuel
plantations: eucalyptus
al. 2012; Drewer et al. 2012; Morrison et al. 2014), and
work on the environmental impacts and benefits of SRF by Forest Research (McKay et al.
2011). The project will provide important evidence that will contribute to the forestry sector
discussion on SRF, and will inform wider UK policy and practice for land-use transitions to
woody bioenergy crops.
Key research questions
(1) Are there significant differences in the magnitudes of bVOC emissions from different SRF
tree species (broadleaf, conifer, exotic) under British conditions?
(2) How much do bVOC emissions from SRF species vary according to climate?
(3) How much could bVOC emissions from SRF contribute to the total UK budget?
Methodology
bVOC emissions will be measured from different tree species being trialled for use in SRF, in
different climates and stand ages within the UK. Existing replicated trials managed by Forest
Research for Forestry Commission Scotland and for Defra across the UK will be used. These
sites cover a range of species including: ash, alder, birch, hybrid aspen, sycamore, sweet
chestnut, and eucalyptus and Nothofagus spp. Trace gas samples will be collected from
vegetation enclosures onto adsorbent tubes (Tenax and Carbotrap) and analysed using GCMS with thermal desorption at CEH Edinburgh. Approximately bi-monthly measurements will
be carried out at selected field sites to capture seasonal variation; concentrating on June-Oct
periods for deciduous species. This will provide seasonal data of bVOC fluxes from different
tree species giving an indication of the variability and potential contribution to the total UK
budget. In addition measurements will be taken at leaf scale in the field and laboratory using
controlled environment leaf cuvettes and branch enclosures. The branch, leaf and litter data
will be used to identify source strength and possible controlling factors for the plantation
species, and laboratory studies will explore abiotic and biotic controls in more detail at leaf
and branch scale for selected species. Results will be scaled up to potential national
emissions using projections of SRF expansion and tree species suitability and productivity.
Training
A comprehensive training programme will be provided comprising both specialist scientific
training and generic transferable and professional skills. The latter includes a programme
focused on personal effectiveness, communication, team building and career management,
as well as courses on safety assessment, project management, literature searching, oral
presentations, poster preparation, and thesis writing. The student will also receive training in
undergraduate laboratory demonstrating and, if they wish, in areas such as schools or public
outreach activities and business skills.
The student will attend relevant atmospheric and ecological courses available in the UoE
Schools of GeoSciences & Chemistry. Specific skills training will include training in analytical
techniques, particularly in gas chromatography and mass spectrometry. The student will
make use of excellent computing facilities within both CEH and UoE, and will gain expertise
in statistical packages (Genstat, Minitab, SigmaPlot, R), and use of spreadsheets (Excel) for
storing and manipulating data. CEH provides underpinning research on a wide range of
environmental sampling programmes and the student will receive professional training in
health and safety during fieldwork, and in obtaining reliable field-based data, permitting them
to design and execute an appropriate sampling regime. The student will also be encouraged
to attend relevant NERC summer schools and to present results at national and international
scientific meetings. The student will also benefit from training at Forest Research Northern
Research Station to access information on SRF practices, trials and long-term experiment
information, and gaining practical experience from researchers in forest science.
Requirements
Candidates should have a good undergraduate or Masters degree in environmental,
chemical or physical sciences, with a strong focus on analytical skills. Willingness to
undertake regular (UK) fieldwork and a driving licence are essential.
References
Copeland, N., Cape, J. N., Heal, M. R. (2012) Volatile organic compound emissions from Miscanthus and short
rotation coppice willow bioenergy crops, Atmospheric Environment 60, 327-335.
Drewer, J., Finch, J. W. et al. (2012) How do soil emissions of N2O, CH4 and CO2 from perennial bioenergy crops
differ from arable annual crops? Global Change Biology Bioenergy 4, 408-419.
Morrison E.C., Drewer, J., Heal, M.R. (2014) A comparison of BVOC fluxes from the perennial bioenergy crops
short-rotation coppice willow and Miscanthus and the annual arable crops wheat and oilseed rape, Global Change
Biology Bioenergy, under review.
McKay, H. (ed.) (2011) Short Rotation Forestry: review of growth and environmental impacts. Forest Research
Monograph, 2, Forest Research, Surrey, 212pp
http://www.forestresearch.gov.uk/pdf/FRMG002_Short_rotation_forestry.pdf/%24file/FRMG002_Short_rotation_forestry.pdf
Project summary
This project will investigate the magnitude and determinants of variations in biogenic VOC
emissions from different species of short-rotation forest that are being proposed in the UK to
provide biomass to fulfil renewable energy requirements.